Recent content by nockieboy

So my FPGA GPU has come on leaps and bounds and now I'm building an FPU into it as well, to speed up the old Mandelbrot drawing and as a precursor to 3D graphics. Part of testing the FPU is getting it to work with BBCBASIC, as it seems to work with floating point maths at its most basic level...

Hi everyone, I'm trying to use LD80 (apparently) to assemble the BBC BASIC source files along with a custom patch.z80 file for my DIY computer. I've finally managed to get the project to build - almost - but the assembly (using ZMAC) is failing with this error: ld80: Unimplemented extension...

Hi everyone, Does anyone know if there is a way of getting an immediate keypress from the user in MBASIC (~version 4) in CP/M? I'm aware of (and using) INPUT to get a character, or sequence of characters, from the user - but this requires a Carriage Return before control is handed back to the...

Okay, I'm nearly there with the conversion from ZMAC assembly to TASM-friendly assembly code. I've just hit the final set of assembly errors and cannot work out how to translate the offending directives to something TASM will understand. The BBC BASIC assembly constitutes a number of...

I've got my custom video card (prototype) working nicely with my DIY Z80 computer now, and I thought I'd tweak the copy of BBC BASIC that I have in CP/M so that it can clear the screen, position the cursor etc. using the (included in the BBC BASIC distribution) BBCDIST.MAC file to use my...

:crazy: Doug, you're a star. :D You've hit the nail on the head. Thanks to your question, I went and checked the INSTALL command in a little more detail, which copies the CPM image from ROM and writes it onto Sector 0 of the CF card. It was only by doing that, that I checked out the CPMLOAD...

CPMSTART may be a label that I've added at some point in the past, or is specific to the copy of CPM source code that I have. It's just a label that is used for the .ORG command to set the address for CBASE. TERMCPM is probably a label I use in my code rather than a generally-accepted label...

Hi all, Context: I'm in the middle of adding my video driver to my CP/M 2.2 BIOS so I can see CP/M on the screen instead of via the console. My computer is DIY, my video card is FPGA DIY, my knowledge of CP/M isn't great as I was too young to use it much when it was a commercial product and...

Hi everyone, As the title suggests, I'm trying to receive a lot of pasted code into a terminal running CP/M 2.2 and would like to receive the data and process it without it being automatically echoed back to the terminal as BDOS function 1 (C_READ) does. I've tried using BDOS function 6...

Well, I didn't expect that! I thought I'd do a little debugging on EXIT.COM as it's not resetting back to the DMI as it should do (probably something I've done wrong.) I'd written the assembly in Magic Wand to try out restricting development to CP/M after my last post, tried running EXIT...

Yes, it's being reset here, right at the start of ld_ccp which is called by cold AND warm boots: ld_ccp: ; Zero the EXT byte/s LD A,0 LD B,4 ; Loop iterations (bytes to clear) LD HL,ccp$fcb+12 clr_lp: LD (HL),A ; Zeros the FCB EXT and other bytes INC HL DJNZ clr_lp...

;) If I knew the code well enough (I'm still learning the system AND the language it's written in), I'd feel happy reviewing and commenting but I'm in the dark with this stuff and relying on the experts - yes, that's you guys! :D So, I've copied the setLBAaddr function from the CP/M 2.2 BIOS...

Here's the latest version of my BIOS3.ASM:

Okay, new log follows with extra debug information. I've added a copy of BIOS3.ASM as well for info so you can see where the debug prints are. I've put a HALT before the jump to CCP to stop the log from repeating constantly (which it is otherwise doing as before.) BIOS: To my...

Oh we don't bother that much either - just spent the evening with the boss's sister and her hubby and the kids. The NASCOM is an intriguing machine - I didn't even know they existed until about a year go when I embarked on building this Z80-based SBC myself. Mind you, I'd have been a little...